boys who gush out about a game like fangirls, but when you call them out on being a fan, act all suprised at you for making such a game. then later on they call you "sad" for playing a game, usually when you've only just started playing the damn game and mentioned a feature you like about it, saying "oh look who's the fangirl now! why don't i get you a costume so you can dress up and play main character".
I also (dis)like the fans who say memes but then claim to have no knowledge of where that meme comes from in order to not appear like a fan, desperatly trying to hide the portal logo on their shirt when saying things about a companion cube usually. i say it as "(dis)like", because i guess i am almost one of these people. i've never played Left For Dead or Team Fortress, but i'll often say things like "that ____ is a spy!" or "PEEEEEEELZ". However, i at least admit that they come from these games and that i know enough about these games that i might as well be a fan, even having not played them. also "(dis)like" because its fun watching them try to impress the non-gamers by being dishonest with themselves.
i don't particularly think i can classify these breeds of fan well, so i won't bother xP
oh, and on a final note. People are always fans of something. Fan seems to have become a derrogatory (mind the spelling) term, meaning that you are a hardcore-don't-ever-want-to-hear-anything-bad-about-it-so-don't-you-dare-say-anything-nasty-or-i-will-spend-half-a-day-educating-you-in-vain-attempt-to-make-you-like-it-too-because-there-is-no-way-i-could-actually-be-wrong. That description is one of a Fan-boy/girl. Fans are usually ordinary people, who will go about liking/loving that one thing and reccomend it if they feel it necessary and can even note the criticisms. like i said, people are always fans of something... unless you just hate everything, inwhich case you have probably already committed suicide, or are now seeing the light that actually, there are some things you like, even if its just the taste of a particular companies butter on your toast in the morning.